Library /sys$common/syshlp/DBG$HELP.HLB  —  DEBUG  Address Expressions
    Several debugger commands require that you specify an address
    expression. An address expression is an entity that denotes a
    memory address or a register. Commands for which you specify
    address expressions are:

       (SET,ACTIVATE,DEACTIVATE,CANCEL) BREAK
       (SET,ACTIVATE,DEACTIVATE,CANCEL) TRACE
       (SET,ACTIVATE,DEACTIVATE,CANCEL) WATCH
       EVALUATE/ADDRESS
       EXAMINE
       DEPOSIT (at the left of the equal sign)

    In general, you can specify address expressions using the syntax
    of the currently set language. For example:

    DBG> EXAMINE A(1)     ! FORTRAN
    DBG> SET WATCH A[1]   ! Pascal
    DBG> EXAMINE C OF R   ! COBOL

    In addition, you can specify address expressions numerically, and
    you can also use the built-in symbols %LINE and %LABEL to refer
    to code locations:

    DBG> EXAMINE 512
    DBG> SET BREAK %LINE 10

    You can also use the following operators to specify addresses
    that you might not be able to access by name (nonsymbolic
    addresses):

    + - *    Arithmetic operators
    /
    @ or .   Indirection
    <p,s>    Select bit field

    For example, examine the instruction 3 bytes after line 10:

    DBG> EXAMINE %LINE 10 + 3

    Examine the location pointed to by P:

    DBG> EXAMINE @P

    Do not confuse an address expression with a language expression,
    which denotes a value rather than a program location. The
    following examples show how the same command parameter is treated
    either as an address expression or as a language expression
    depending on the command:

    Show the address of the variable X (address expression):
    DBG> EVALUATE/ADDR X
    512
    Show the current value of X (address expression):
    DBG> EXAMINE X
    X: 0
    Evaluate X (language expression):
    DBG> EVALUATE X
    0
    Evaluate X+1 (language expression):
    DBG> EVALUATE X+1
    1
    Show value at location X plus 1 byte (address expression):
    DBG>  EXAMINE X+1
    513: 0
Additional Information: explode extract
Using Symbols and Operators in Address Expressions
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